/* 广告 */
body,
html {
  width: 100%;
  height: 100%;
}
body {
  background-image: url('../img/advertisement-bg.jpg');
  background-repeat: no-repeat;
  background-size: cover;
  background-position: center top;
}
.berder_nav {
  height: 40px;
  background-color: #fff;
  text-align: center;
  line-height: 40px;
}
/* 时间盒子 */
.big_box {
  display: flex;
  justify-content: flex-end;
}
.time_box {
  width: 105px;
  height: 40px;
  background-color: #fff;
  text-align: center;
  line-height: 40px;
  border-radius: 20px;
  margin-top: 20px;
  margin-right: 20px;
}
@keyframes run {
  0% {
    transform: translateY(-200px);
    opacity: 0;
  }
  100% {
    transform: translateY(0px);
    opacity: 1;
  }
}
.footer {
  margin-top: 100%;
}
.txt_key {
  opacity: 1;
  text-align: center;
  animation: run 3s;
}
